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Within HRI, we assert that collaboration fundamentally hinges on communication, wherein agents share information to achieve common objectives. Information theory provides a rigorous mathematical framework for quantifying the flow of information within communicating agents. It serves as a unifying framework for evaluating the dynamic interplay of various communication channels in pHRI. This study introduces a non-parametric approach based on information entropy to assess communication between agents in pHRI scenarios and detect important behaviors, such as information flow, leadership, and coupling. Through a comprehensive experimental setup involving collaborative catching tasks, we demonstrate the versatility and applicability of the proposed methodology.<\/jats:p>","DOI":"10.1145\/3744755","type":"journal-article","created":{"date-parts":[[2025,6,20]],"date-time":"2025-06-20T10:47:17Z","timestamp":1750416437000},"page":"1-35","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["A Non-parametric Approach to Exploring and Quantifying the Information Flow in Human\u2013Robot Collaboration"],"prefix":"10.1145","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0403-991X","authenticated-orcid":false,"given":"Gustavo Jose","family":"Giardini Lahr","sequence":"first","affiliation":[{"name":"Human-Robot Interfaces and Interaction, Italian Institute of Technology, Genova, Italy and Instituto Israelita de Ensino e Pesquisa, Hospital Israelita Albert Einstein, Sao Paulo, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7954-6764","authenticated-orcid":false,"given":"Doganay","family":"Sirintuna","sequence":"additional","affiliation":[{"name":"Human-Robot Interfaces and Interaction, Italian Institute of Technology, Genova, Italy and Department of Informatics, Bioengineering, Robotics, and System Engineering, University of Genoa, Genoa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2413-3962","authenticated-orcid":false,"given":"Francesco","family":"Tassi","sequence":"additional","affiliation":[{"name":"Human-Robot Interfaces and Interaction, Italian Institute of Technology, Genova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9896-8217","authenticated-orcid":false,"given":"Heni Ben","family":"Amor","sequence":"additional","affiliation":[{"name":"School of Computing and Augmented Intelligence, Arizona State University, Tempe, Arizona, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1261-737X","authenticated-orcid":false,"given":"Arash","family":"Ajoudani","sequence":"additional","affiliation":[{"name":"Human-Robot Interfaces and Interaction, Italian Institute of Technology, Genova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"320","published-online":{"date-parts":[[2025,8,20]]},"reference":[{"issue":"5","key":"e_1_3_3_2_2","doi-asserted-by":"crossref","first-page":"957","DOI":"10.1007\/s10514-017-9677-2","article-title":"Progress and prospects of the human-robot collaboration","volume":"42","author":"Ajoudani Arash","year":"2018","unstructured":"Arash Ajoudani, Andrea Maria Zanchettin, Serena Ivaldi, Alin Albu-Sch\u00e4ffer, Kazuhiro Kosuge, and Oussama Khatib. 2018. 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